A so-called “wireless network” uses radio waves as the signal transmission medium. In Taiwan, the most widely used wireless network signals nowadays are Wi-Fi signals and 3G signals, so mobile terminal devices (e.g., smart phones and tablet personal computers) are typically equipped with a wireless module configured for receiving these two types of signals.
The Wi-Fi and 3G technologies are briefly summarized as follows. Wi-Fi, which is based on the IEEE 802.11 standard, features low-cost and easy installation and is therefore extensively applied to the creation of wireless network environments in schools, enterprises, and government institutions. As Wi-Fi signals have a transmission range of only 100 meters or so, it is common practice for service providers to set up “hotspots” in places which are generally crowded (e.g., airports, train stations, coffee shops, and libraries). One who carries a mobile terminal device capable of receiving Wi-Fi signals and enters the radio signal transmission range of a “hotspot” can readily connect to the Internet through the “hotspot”.
On the other hand, 3G stands for “the third generation of mobile telecommunications technology” and supports cellular mobile communication for high-speed data transfer (i.e., the IMT-2000, or International Mobile Telecommunications-2000, specifications). 3G can be used to integrate wireless communication with the Internet and other multimedia communication technologies in order to deal with image, music, and video data and provide such services as webpage browsing, teleconference, and electronic commerce. As 3G enables high-speed download, and with the increasing prevalence of smart phones and tablet personal computers, 3G signals are now commonly used in wireless network connection, and because of that, 3G networks are frequently overloaded, which leads to low service quality and customer complaints.
To overcome this problem, most mobile terminal devices are designed to be switchable between Wi-Fi signals and 3G signals, and in light of this, many telecommunication service providers try to divert data flow from 3G networks by deploying a large number of “hotspots”, which allow 3G users to connect to the Internet through Wi-Fi signals instead. While this diversion scheme can effectively reduce the number of mobile terminal devices using 3G networks, the following problem arises. As is well known in the art, one who wishes to use the network services of a “hotspot” must select the service set identifier (SSID) of a currently available “hotspot” and input the corresponding password in order to connect to that specific “hotspot” and use its network services. However, this operation can be difficult to perform because a mobile terminal device can often find a good number of SSIDs, which are not necessarily the SSIDs of “hotspots” but also include the SSIDs of private wireless networks. As the list of access points available to a mobile terminal device (i.e., the list showing the SSIDs) tends to be extremely long, the user of the mobile terminal device may have problem identifying and selecting the SSID available for use. This may in turn reduce the user's willingness to use “hotspots”, and the user may keep using the 3G services simply to avoid the trouble stated above. If this problem persists, the aforesaid diversion scheme will eventually fail.
Therefore, it has been an important goal in the related industries to find an effective solution to the foregoing problem so that one can rapidly and conveniently obtain the information of a “hotspot” and connect a mobile terminal device to the “hotspot”.